The invention relates to a machine for extracorporeal blood treatment.
Specifically, though not exclusively, the machine can be usefully applied in a machine for treatment of renal insufficiency, and/or for therapeutic replacement of plasma, and/or for hemoperfusion.
As is known, a machine for extracorporeal blood treatment is operatively associated to a circuit for extracorporeal blood treatment. Also well known is an injection system of an anticoagulant liquid into an extracorporeal circuit for reducing a risk of coagulation in the extracorporeal circuit. The injection system usually comprises a syringe pump for injection of relatively low and precise flows of anticoagulant. The syringe pump generally comprises a removable syringe, a support predisposed on the front panel of the machine for receiving and removably holding the syringe in position, a linear pusher for moving the syringe plunger, a sensor for emitting a signal indicating the push force exerted on by the pusher, and a control unit for receiving the above-mentioned signal and for guiding the linear pusher in accordance with the signal received.
One of the problems of known-type machines for extracorporeal blood treatment consists in the adaptability thereof to syringes of various sizes. The syringe supports used at present enable safe and reliable mounting of a relatively limited range of syringes. Also, when the syringe size is changed, the position of the longitudinal axis of the syringe changes with respect to the pusher; consequently it is necessary to take this change into consideration when calculating the thrust force the pusher must exert in order to obtain the desired anticoagulant flow rate. A further problem is ascertaining surely and reliably the type of syringe which is in use by the syringe pump, in order to prevent errors in the anticoagulant flow rate which might turn out to be considerably dangerous for the patient.